This invention relates to the injection of fuel into internal combustion engines and more particularly to new and improved fuel injector nozzles which provide variable fuel spray depths and patterns to match varying engine loads and automatic closure of the nozzle for sealing the nozzle from combustion chamber gas intrusion between fuel injection events to provide near zero sac volume.
Various nozzle designs have been employed in fuel injection systems to provide finely atomized fuel spray patterns injected into engine combustion chambers to improve combustion and engine operation efficiency. An illustrative example of one such design is disclosed by E. F. Obert in the publication "International Combustion Engine Analysis and Practice" 2nd edition, 1950, International Textbook Company, Scranton, Pa. FIGS. 12-18, p. 386, hereby incorporated by reference. The present invention is of the general category of that disclosed in the above-referenced publication in that highly reliable in-cylinder fuel injection is provided, but further provides differing atomized fuel injection spray patterns and depths to match engine loads for optimized engine efficiency and without having significant sac volumes which generally result in undesirable high hydrocarbon emissions.